Apparatus for making tubes from ingots



S, OKANO.

APPARATUS FOR MAKING TUBES FROM INGOTS.

APPLRCATION FILED mac. 24. 1919.

. 1,413,605,, Patented Apr. 25, 1922.

Zli

snakin tubes from ingots.

@QTAR on, or nausea-1i no, sense,

sense nouns, JAPAN.

J's-sun, nssienon ro arson nouwa'u MLWI) mastication it coin ination of a set oil rolls a pair of semicircularly grooved rolls and mandrel the head of which terminates with an edge but is gradually rounded towards its rear art.

7 The object of this invention is to obtain of s eel and other metal loy using cornparatively small force and with sininle equipment and work, thus economiaing labor and expense.

In the accompanying drawin Fig. 1 shows a side view of a combination of a set of rolls with a pair semicircularly grooved rolls.

Fig. 2 is a plan view of O a, showing an ingot being formed into a tube by means oi the semicircularly grooved role a mandrel, as the said ingot is being the last rolls.

Fig. 3 is a side view of F 52..

Figs. 4 and 5 are respectively "slate and side views of the mandrel.

6 shows an ingot cut slit; and

Figs. 7 and 8 show the same it i" reduced in thickness by successive passage between the series of rolls.

This apparatus is intended for use in carrying out a new process ofinanutacturing metallic tubes from ingots, consisting in cutting an axial slit through an ingot, rolling the ingot to about twice the thickness of the wallof the tube to be manufactured, and forming the flat ingot into a tube by means of a mandrel and a pair of grooved rolls, taking advantage of the force with which the ingot is forced out of the reducing rolls.-

To describe my invention in detail, on a frame a, three rolls b, c and with an axial d are mounted which are revolved by means of toothed wheels ad and 9 through arms h, i and j, and are a justable as to spaces between them ecording to the thickness to which the ingot specification of Letters Eatcnt' ingot leaving Patented Apr."%5 392%.

is to be rolled. The nunuher of rolls can of course be increased to flour or more it regu-ired.

in front oi the lowest pair (2 and 05 of the rolls are mounted another pair of rolls 7:: it, revolved by any suitable mechanism. Each of these rolls t is semicircularly grooved, so a circular space,' the diann etc-r of which is to the outer diameter of the tube to be manufactured is left between these.

The mandrel is shaped something like an front end with an terminating at the at but gradually rounded toward the parts 2,, diameter of the rounded m" being equal to oi the tubes to be made. This mandrel 1S fixed to a long rod n in such a way that the rounded part no lies in the circular space left between the grooved rolls, the distance between the mandrel and the rolls being equal to the thickness oi": the wall of the tube to be manufactured.

til

the inner diameter To manufacture steel tubes with this apnaratus, first cut an axial slit g0 throughan spaces as an, uncut on'both the s each equal to or a little larger than, tl lc ness got the tube 7* to be manufactured. 'l roll the ingot thus cut with a slit, with the rolls 1) and 0 several tire-es, reducing the ingot ually to then to gm and so on, until t; ie is oiotained, by adjusting the between the said rolls at each rolling as required. When the ingot is to be rolled tor the last time, that is, to reduce the ingot to such a degree that the thickness trom the central slit is equal to, or a little greater than, the thickness of the wall oi? the tube to be manufactured, the in 0t should be passed between the rolls 0 an 02, and as it passes from the said rolls, the edge of the mandrel should be inserted in the slit. Then the mandrel, which is firmly fixed, will open the fiat ingot'into a tube, its rounded part shaping the bore of the tube. At the. same time the grooved rolls, between which the ingot passes, form the outer sha e of the tube. Thus, the energy with whic the flat ingot is forced out of the last rolls, and over the mandrel and between the grooved rolls, will shape it into a perfect tube.

in thickness grad- Mill According to the process heretofore conimonly used, a mandrel is forced into a solid ingot and a bore made therethrough, the ingot thus pierced with a bore, being then rolled into a tube. Thus great power, and extensivemechanical and other equipment, are required, which makes the work of tube mak ing very expensive, and as a matter of fact, it is impracticable for a factory on a small scale to undertake it.

However, if the apparatus .of my invention is used, as an axial slit is cut through an ingot, which is then repeatedly rolled until it is reduced to the re uired thickness, and as the ingot thus rolled and reduced is formed into a tube by a mandrel and a pair of grooved rolls, taking advantage of the force with Which the ingot is forced out of the last rolls, the power and expense can be greatly economized. Moreover, the work of boring an ingot'and that of rolling it into a tube can be done at once, and tubes of uniform quality and size can be manufactured with comparatively greater rapidity and with equipment on a smaller scale.

I wish it understood that my apparatus end correspon ing approximately with the size of the slit and tapering to a clrcular sec-' tion at its rear end corresponding with the interior of the tube to be formed, and a'pair can be modified in plan without departing V An apparatus for manufacturing metal at,

of semicircularly grooved" shaping rolls having the groove radius e ual to the radius of the tube to be formed, said two pairs of rolls being disposed axially perpendicular to each other.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

SOTARO OKANO. Witnesses: V

W. EHIHARAH, Y. HIRAIWA, 

